Hello, syzbot found the following issue on: HEAD commit: 940fcc189c51 Add linux-next specific files for 20230921 git tree: linux-next console+strace: https://syzkaller.appspot.com/x/log.txt?x=158b9424680000 kernel config: https://syzkaller.appspot.com/x/.config?x=1f140ae6e669ac24 dashboard link: https://syzkaller.appspot.com/bug?extid=477d8d8901756d1cbba1 compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40 syz repro: https://syzkaller.appspot.com/x/repro.syz?x=120e0dba680000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=12f3767a680000 Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/b8921b235c24/disk-940fcc18.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/c80a9f6bcdd4/vmlinux-940fcc18.xz kernel image: https://storage.googleapis.com/syzbot-assets/ed10a4df6950/bzImage-940fcc18.xz The issue was bisected to: commit 44ef23e481b02df2f17599a24f81cf0045dc5256 Author: Amir Goldstein <amir73il@xxxxxxxxx> Date: Wed Aug 16 13:47:59 2023 +0000 ovl: do not encode lower fh with upper sb_writers held bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=1364cda6680000 final oops: https://syzkaller.appspot.com/x/report.txt?x=10e4cda6680000 console output: https://syzkaller.appspot.com/x/log.txt?x=1764cda6680000 IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+477d8d8901756d1cbba1@xxxxxxxxxxxxxxxxxxxxxxxxx Fixes: 44ef23e481b0 ("ovl: do not encode lower fh with upper sb_writers held") RAX: ffffffffffffffda RBX: 00007ffd8d25ca30 RCX: 00007f15a9d353e9 RDX: 00007f15a9d344b0 RSI: 00007ffd8d25ca30 RDI: 0000000020000200 RBP: 0000000000000002 R08: 00007ffd8d25c7a6 R09: 00007ffd8d2d51a0 R10: 0000000000000002 R11: 0000000000000246 R12: 00007ffd8d25ca2c R13: 00007ffd8d25ca70 R14: 00007ffd8d25ca50 R15: 0000000000000002 </TASK> ================================================================== BUG: KASAN: invalid-free in slab_free mm/slub.c:3809 [inline] BUG: KASAN: invalid-free in __kmem_cache_free+0xb8/0x2d0 mm/slub.c:3822 Free of addr ffff888078b14650 by task syz-executor360/5060 CPU: 0 PID: 5060 Comm: syz-executor360 Not tainted 6.6.0-rc2-next-20230921-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/04/2023 Call Trace: <TASK> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd9/0x1b0 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:364 [inline] print_report+0xc4/0x620 mm/kasan/report.c:475 kasan_report_invalid_free+0xab/0xd0 mm/kasan/report.c:550 ____kasan_slab_free+0x1a0/0x1b0 mm/kasan/common.c:216 kasan_slab_free include/linux/kasan.h:164 [inline] slab_free_hook mm/slub.c:1800 [inline] slab_free_freelist_hook+0x114/0x1e0 mm/slub.c:1826 slab_free mm/slub.c:3809 [inline] __kmem_cache_free+0xb8/0x2d0 mm/slub.c:3822 ovl_do_copy_up fs/overlayfs/copy_up.c:973 [inline] ovl_copy_up_one+0x15ac/0x3250 fs/overlayfs/copy_up.c:1137 ovl_copy_up_flags+0x189/0x200 fs/overlayfs/copy_up.c:1192 ovl_nlink_start+0x391/0x470 fs/overlayfs/util.c:1144 ovl_do_remove+0x16d/0xd50 fs/overlayfs/dir.c:893 vfs_unlink+0x2f1/0x900 fs/namei.c:4313 do_unlinkat+0x3da/0x6d0 fs/namei.c:4379 __do_sys_unlink fs/namei.c:4427 [inline] __se_sys_unlink fs/namei.c:4425 [inline] __x64_sys_unlink+0xc8/0x110 fs/namei.c:4425 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f15a9d353e9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 17 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ffd8d25ca08 EFLAGS: 00000246 ORIG_RAX: 0000000000000057 RAX: ffffffffffffffda RBX: 00007ffd8d25ca30 RCX: 00007f15a9d353e9 RDX: 00007f15a9d344b0 RSI: 00007ffd8d25ca30 RDI: 0000000020000200 RBP: 0000000000000002 R08: 00007ffd8d25c7a6 R09: 00007ffd8d2d51a0 R10: 0000000000000002 R11: 0000000000000246 R12: 00007ffd8d25ca2c R13: 00007ffd8d25ca70 R14: 00007ffd8d25ca50 R15: 0000000000000002 </TASK> Allocated by task 5060: kasan_save_stack+0x33/0x50 mm/kasan/common.c:45 kasan_set_track+0x25/0x30 mm/kasan/common.c:52 __kasan_slab_alloc+0x81/0x90 mm/kasan/common.c:328 kasan_slab_alloc include/linux/kasan.h:188 [inline] slab_post_alloc_hook mm/slab.h:762 [inline] slab_alloc_node mm/slub.c:3478 [inline] slab_alloc mm/slub.c:3486 [inline] __kmem_cache_alloc_lru mm/slub.c:3493 [inline] kmem_cache_alloc_lru+0x215/0x670 mm/slub.c:3509 __d_alloc+0x32/0xac0 fs/dcache.c:1768 d_alloc+0x4e/0x220 fs/dcache.c:1848 lookup_one_qstr_excl+0xc7/0x180 fs/namei.c:1604 do_unlinkat+0x294/0x6d0 fs/namei.c:4365 __do_sys_unlink fs/namei.c:4427 [inline] __se_sys_unlink fs/namei.c:4425 [inline] __x64_sys_unlink+0xc8/0x110 fs/namei.c:4425 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x63/0xcd Last potentially related work creation: kasan_save_stack+0x33/0x50 mm/kasan/common.c:45 __kasan_record_aux_stack+0xbc/0xd0 mm/kasan/generic.c:492 __call_rcu_common.constprop.0+0x9a/0x790 kernel/rcu/tree.c:2653 dentry_free+0xc2/0x160 fs/dcache.c:377 __dentry_kill+0x4c1/0x640 fs/dcache.c:621 dentry_kill fs/dcache.c:745 [inline] dput+0x6de/0xf80 fs/dcache.c:913 handle_mounts fs/namei.c:1554 [inline] step_into+0x1192/0x2230 fs/namei.c:1839 walk_component+0xfc/0x5a0 fs/namei.c:2007 lookup_last fs/namei.c:2458 [inline] path_lookupat+0x17f/0x770 fs/namei.c:2482 filename_lookup+0x1e7/0x5b0 fs/namei.c:2511 vfs_statx+0x160/0x430 fs/stat.c:240 vfs_fstatat+0xb3/0x140 fs/stat.c:295 __do_sys_newfstatat+0x98/0x110 fs/stat.c:459 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x63/0xcd The buggy address belongs to the object at ffff888078b145e0 which belongs to the cache dentry of size 312 The buggy address is located 112 bytes inside of 312-byte region [ffff888078b145e0, ffff888078b14718) The buggy address belongs to the physical page: page:ffffea0001e2c500 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x78b14 head:ffffea0001e2c500 order:1 entire_mapcount:0 nr_pages_mapped:0 pincount:0 ksm flags: 0xfff00000000840(slab|head|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000000840 ffff88814000a8c0 ffffea0001e2d080 dead000000000003 raw: 0000000000000000 0000000000150015 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 1, migratetype Reclaimable, gfp_mask 0xd20d0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_RECLAIMABLE), pid 4515, tgid 4515 (udevd), ts 47959600386, free_ts 28011797989 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x2cf/0x340 mm/page_alloc.c:1530 prep_new_page mm/page_alloc.c:1537 [inline] get_page_from_freelist+0xf17/0x2e50 mm/page_alloc.c:3200 __alloc_pages+0x1d0/0x4a0 mm/page_alloc.c:4456 alloc_pages+0x1a9/0x270 mm/mempolicy.c:2305 alloc_slab_page mm/slub.c:1870 [inline] allocate_slab+0x251/0x380 mm/slub.c:2017 new_slab mm/slub.c:2070 [inline] ___slab_alloc+0x8c7/0x1580 mm/slub.c:3223 __slab_alloc.constprop.0+0x56/0xa0 mm/slub.c:3322 __slab_alloc_node mm/slub.c:3375 [inline] slab_alloc_node mm/slub.c:3468 [inline] slab_alloc mm/slub.c:3486 [inline] __kmem_cache_alloc_lru mm/slub.c:3493 [inline] kmem_cache_alloc_lru+0x4e1/0x670 mm/slub.c:3509 __d_alloc+0x32/0xac0 fs/dcache.c:1768 d_alloc+0x4e/0x220 fs/dcache.c:1848 d_alloc_parallel+0xe9/0x12d0 fs/dcache.c:2637 lookup_open.isra.0+0xaa4/0x13b0 fs/namei.c:3401 open_last_lookups fs/namei.c:3544 [inline] path_openat+0x931/0x29c0 fs/namei.c:3774 do_filp_open+0x1de/0x430 fs/namei.c:3804 do_sys_openat2+0x176/0x1e0 fs/open.c:1422 do_sys_open fs/open.c:1437 [inline] __do_sys_openat fs/open.c:1453 [inline] __se_sys_openat fs/open.c:1448 [inline] __x64_sys_openat+0x175/0x210 fs/open.c:1448 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1130 [inline] free_unref_page_prepare+0x476/0xa40 mm/page_alloc.c:2342 free_unref_page+0x33/0x3b0 mm/page_alloc.c:2435 free_contig_range+0xb6/0x190 mm/page_alloc.c:6372 destroy_args+0x7c9/0xa10 mm/debug_vm_pgtable.c:1028 debug_vm_pgtable+0x1d79/0x3e00 mm/debug_vm_pgtable.c:1408 do_one_initcall+0x11c/0x640 init/main.c:1232 do_initcall_level init/main.c:1294 [inline] do_initcalls init/main.c:1310 [inline] do_basic_setup init/main.c:1329 [inline] kernel_init_freeable+0x5c2/0x8f0 init/main.c:1547 kernel_init+0x1c/0x2a0 init/main.c:1437 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304 Memory state around the buggy address: ffff888078b14500: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff888078b14580: 00 00 00 00 fc fc fc fc fc fc fc fc 00 00 00 00 >ffff888078b14600: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ^ ffff888078b14680: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff888078b14700: 00 00 00 fc fc fc fc fc fc fc fc 00 00 00 00 00 ================================================================== --- This report is generated by a bot. It may contain errors. See https://goo.gl/tpsmEJ for more information about syzbot. syzbot engineers can be reached at syzkaller@xxxxxxxxxxxxxxxx. syzbot will keep track of this issue. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot. For information about bisection process see: https://goo.gl/tpsmEJ#bisection If the bug is already fixed, let syzbot know by replying with: #syz fix: exact-commit-title If you want syzbot to run the reproducer, reply with: #syz test: git://repo/address.git branch-or-commit-hash If you attach or paste a git patch, syzbot will apply it before testing. If you want to overwrite bug's subsystems, reply with: #syz set subsystems: new-subsystem (See the list of subsystem names on the web dashboard) If the bug is a duplicate of another bug, reply with: #syz dup: exact-subject-of-another-report If you want to undo deduplication, reply with: #syz undup
